Context Engine plugins for Claude Code

A Claude Code plugin marketplace with one plugin, context-engine. It gets Claude Code, and the subagents it starts, to use Context Engine's indexed code search instead of grepping the repo.

Install

claude plugin marketplace add Context-Engine-AI/claude-plugins
claude plugin install context-engine@context-engine-ai --scope user

Or run ctxce setup claude from the Context Engine CLI (ctxce setup claude --uninstall removes it).

The plugin does not add an MCP server. It works with the context-engine MCP server that ctxce or the Context Engine extension already configured, so tool names stay mcp__context-engine__*.

What it does

The hooks act only when both of these are true. Otherwise they print nothing and change nothing.

• The workspace maps to a Context Engine collection. The plugin reads the mappings ctxce keeps under ~/.ctxce/workspaces/, a ctx_config.json in the repo, or CTXCE_COLLECTION.
• A Context Engine MCP server is configured for the session: ~/.claude.json (user or local scope), the repo's .mcp.json once approved, or --mcp-config (with --strict-mcp-config respected).

SessionStart and SubagentStart. Adds a short factual note (under 600 characters): the collection, and when repo_search, symbol_graph or grep fits. SubagentStart matters because Explore and Plan don't read CLAUDE.md.

PreToolUse on Bash, Grep and Glob. It looks at each search locally, with no network calls, in a few milliseconds. A grep for an identifier or a concept across the indexed repo is denied, and the reason gives the exact Context Engine call to make instead:

Not run. Context Engine has this workspace indexed (collection admin_demo-1a2b3c4d).
mcp__context-engine__symbol_graph {"symbol":"parseConfig","query_type":"definition","collection":"admin_demo-1a2b3c4d"}
returns where parseConfig is defined with exact lines in one call (query_type "callers" lists its callers);
mcp__context-engine__repo_search {"query":"parseConfig","collection":"admin_demo-1a2b3c4d"} returns the code
that uses it as verified source.

• At most 2 denies per session, and none once the session has called a Context Engine tool or edited a file (a PostToolUse hook records that). A search that was already denied runs if Claude tries it again.
• Never denied:
  • searches scoped to named files, or to paths outside the repo or in node_modules, vendor, target, dist and similar;
  • counts (-c, | wc), greps that filter piped input, and greps whose matches feed xargs, sed, while read and similar (renames, batch edits);
  • -v, -L, -q, --no-ignore, --hidden, and non-code file types (--include=*.md, -t json);
  • patterns that are real regexes, under 4 characters, numbers, URLs, paths, file names, TODO/FIXME markers, keywords only, or -F literal phrases;
  • git grep against a revision or next to git log/show/diff, and anything with $(...) or a heredoc;
  • a Glob, unless it guesses at a multi-part name such as **/*AuthService*.
• Any error, timeout or unreadable input means the tool call goes ahead unchanged.

State is a few small marker files per session in $TMPDIR/ctxce-claude-hooks-<uid>/.

Switches

• CTXCE_HOOKS=0: turn every hook off.
• CTXCE_REDIRECT=0: keep the session notes, never deny.

Develop

Node 18 or later, no dependencies.

node --test
claude --plugin-dir ./context-engine    # load the working copy without installing
claude plugin validate .